Steganography is the art and science of communicating in a way which hides the existence of the communication. This is in contrast to cryptography in which a third party may detect a message but presumably can not decipher it. The goal of steganography is to hide messages inside otherwise innocuous messages in such a way that the message reader is not even aware that a second secret message is present.
It is a sad fact that certain individuals and entities commonly reproduce the work of others and then sell the copies. Such piracy costs many industries and individuals millions of dollars of lost profits due to their inability to detect or trace such piracy. An advantageous aspect of the invention facilitates protection of such materials. For example, an image can be protected from potential piracy or other unauthorized use by inserting a traceable image into the image. In one example, it may be desirable to insert a certain trademark image into an image. The trademark image is inserted such that it is not visible by ordinary users and does not significantly degrade visual image quality, but if one has an appropriate decoding method, the trademark image can be located and viewed. Such methods are often referred to as “watermarking” or “fingerprinting”. Such techniques are useful in combating piracy of protected materials. Current methods and apparatus used for accomplishing such watermarking (as well as steganography in general) are time intensive and require expensive software.
There is a need for apparatus and methods for automatically accomplishing steganography without seriously degrading image quality. Method and apparatus embodiments constructed in accordance with the principles of the present invention are intended to solve these and other problems.